Cushioning dunnage is used as a protective packaging material when shipping an item in a container. The dunnage fills any voids and/or cushions the item in the container during shipping. Typical materials for forming cushioning dunnage include paper and plastic. Relatively complicated machines and methods are known for producing cushioning dunnage comprising resilient pillow-like strips from rolls of stock material. One such known machine is disclosed in U.S. Pat. No. 5,785,639. The known machines are disadvantageous in that they are suitable primarily for larger-scale productions and they are relatively expensive. There has long been a need in the packaging industry for a small and inexpensive device that creates and dispenses paper or other material for use as void fill and cushioning when shipping products in boxes or other containers.
One common method of supplying material for making a cushioning product is to dispense the material from a roll of material by pulling the material to unwind it from the roll. U.S. Pat. No. 5,749,539 discloses a relatively complex mandrel assembly for mounting a roll of material onto a mounting frame at a supply end of a dunnage conversion machine. This prior art mandrel assembly requires a spindle which extends through the length of the roll and about which the roll rotates on plugs mounted on the roll and carried rotatably by the spindle. This known arrangement does not provide the ability to apply tension to the material roll except for whatever rotational friction is generated between the spindle, which is fixed to the mounting frame, and the plugs which rotate freely about the fixed spindle. In the absence of tension, material backlash may occur when the drive motor is stopped to cut the material.
Excess backlash can separate the material from the forming mechanism, reducing the forming and shaping capabilities of the machine, producing an unsatisfactory product. That is, the roll of material can keep turning even after the material has suddenly stopped being pulled forward which causes the material to lose tension and slacken, and extra material to hang loosely from the roll. Then when the material is quickly pulled forward again, the slack is taken out before the roll begins turning, causing the material to rip.
One proposed solution to this problem, disclosed in U.S. Pat. No. 6,179,765, is to provide jam cleats which are spring biased against mandrel handles of the mandrel assembly to apply a predetermined amount of friction against the mandrel handle. This arrangement is relatively complex and costly and does not account for variations in the necessary frictional force required for rolls of different material or weight, or for changes in the weight of the roll as the material is unwound/dispensed therefrom. There is a need for an improved roll tensioner, and an apparatus, a system and a method for making a cushioning product, which are compact, simple, low cost, and which automatically apply frictional resistance to rotation of the roll being unwound in accordance with the required frictional force for efficient operation.